Revolts need help

[DRIFTER anonymous]

Just want to know if aquaducts, gyms, music halls etc make a difference when it come to cultural penalty? Another example is the tomb of alexander. Playing as saka should i destroy it? Plus what make a gen an interloper? Some of my gens that way outside my region dont have that trait and other do close to home. Any tips on handling an huge empire with saka. Seems like im dealing with revolts half the time.

[athanaric]

Just want to know if aquaducts, gyms, music halls etc make a difference when it come to cultural penalty?

Everything does. However the most important factor is the governor's palace.
When it comes to the other buildings, you'll have to look whether their advantages (like bonus to public order via happiness) outweigh the potential culture penalty they convey. Usually they do, and you should leave them in place. Especially buildings that allow you to hold races or other competitions. And any building that conveys a law bonus (usually paved roads, large stone walls, garrisons), and theatres - they can give your generals really helpful ancillaries for dealing with public order issues.
Obviously you should destroy any foreign building that does not have any effect for your particular faction - for example, colonies are useless for Saka (but not for Pahlava). Temples beyond a certain level (usually higher than tier 4) don't convey any bonuses for the "Barbarian" and Nomad factions, in which case you're better off destroying them and building a Saka temple in place, preferrably the one that grants you the biggest bonus to law (because that also reduces corruption).

Another example is the tomb of alexander. Playing as saka should i destroy it?

AFAIK it bestows a happiness bonus, so you should leave it in place. You'll need every little bonus you can get.

Plus what make a gen an interloper?

Being in a settlement with a Type IV government.

Any tips on handling an huge empire with saka. Seems like im dealing with revolts half the time.

I know, late game with Saka sucks. You can compensate to some degree with Buddhist monasteries (they take an eternity to build but can give you a sizeable happiness bonus). You also want to have Pastoralism as government in most of your cities, and Type IV (Allied Government) in some central places that are good for regional units, for example Taksashila, Seleukeia, Antiocheia. Nomadism is only good for steppe or desert regions, and its only advantage over the two others is better light cavalry recruitment options.
When taking settlements, prioritize those with advanced mines, paved roads, and/or ports. Those structures are the main money makers in EB. Paved roads are also important because of the law bonus, and for extra movement points.